Electrically conductive and optically active polymers have been known for many years. Examples of electrically conductive polymers include polythiophene, polypyrrole and polyaniline. Recently, there has been an increased interest in development of such polymers for application to a wide range of uses, such as, for example, light-weight energy storage devices, electrolytic capacitors, anti-static and anti-corrosive coatings for smart windows and biological sensors. However, the application of electrically conductive and optically active polymers has been limited by some fundamental properties of monomers employed to form these polymers and by processing limitations that limit the quality of the resulting polymers.
Among the most limiting problems of electrically conductive and optically active polymers is their lack of water solubility. Typically, therefore, these polymers are formed in an organic solvent. Attempts to increase the water solubility of these polymers have included derivatization of the polymer following its formation. However, derivatization of electrically conductive and optically active polymers requires several steps and generally proceeds under relatively harsh reaction conditions including, for example, use of fuming sulfuric acid. Further, such derivatization typically results in only partial substitution and, therefore, the improvement in water solubility is limited. In addition, polymers typically degrade during the derivatization, thereby further limiting the effectiveness of post-reaction attempts to improve water solubility.
Another attempt to improve the water solubility of electrically conductive and optically active polymers has been derivatization of monomers and subsequent polymerization in an organic solvent. However, the polymerization rate of derivatized monomers is typically diminished.
Most recently, enzymes, and most notably, horseradish peroxidase, have been employed to accelerate the reaction rate of derivatized monomers. Nevertheless, such reactions, in the context of an organic solvent, generally must be conducted at a relatively low pH. Further, generation of water molecules as a consequence of enzyme catalyzed reactions has typically required that such reactions be conducted in the context of a two-phase reaction system of aqueous micelles. Use of micelles generally limits the polymerization of the polymer and presents additional problems with processing the polymer product, due to the two-phase nature of the reaction system.
Therefore, a need exists to overcome or minimize the above-referenced problems associated with formation of water-soluble electrically conductive and optically active polymers.